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• • I. EXECUTIVE SUMMARY The Cooley Gravel Company (Cooley} of Lakewood, Colorado, a wholly owned subsidiary of CAMAS America, Inc. (CAMAS), is submitting the following document in order to apply fur an amendment to Permit rr 73-21 which grants approval for mining operations at the Morrison Quarry in Jefferson County, Colorado. The proposed amendment would permit Cooley to: Incorporate raw water storage reservoirs in the Central and North Quazry areas as part of reclamation; Expand the limits of mining and limits of disturbance in the North Quarry; Expand the limits of disturbance to the east in the Central and South Quarries; 4. Effect remediation of the east highwall in the existing Central Quarry area; Revise bench and highwall configurations for the existing North and Central Quarries and the formerly proposed South Quazry co accommodate the proposed reservoirs; 6. Institute operational controls, including ongoing geotechnical studies, which will allow mining to proceed while reducing the potential for future slope instability problems such as have occurred in the past; • 7. Allow mining bottom elevations different than previously proposed. The total additional disturbed land will be approximately 50 acres and the new disturbed Jand total will then be 184 acres. The amendment will allow mining to new bottom elevations of EI 5770 ft in the North Quarry, EI 6360 ft in the Centra! Quazry, and 6000 ft in the South Quarry. The base map for the quarry is based on aerial photography which was digitized to generate a topographic map. Mapping based on 17 August 1994 aerial photography of the Central Quazry was spliced into mapping based on 28 April 1993 aerial photography resulting in a recent and accurate topographic map of the entire quarry. Note that between these two mapping episodes, mining occurred only in the Central Quarry and, therefore, this is the only area requiring an update. The existing topography of the azea is shown on Figure C-2, Exhibit C-Premising Plan. This figure shows the April 1993/August 1994 topography depicting the results of mining and reclamation activities to date under the current permit and amendments. This map was used as the base map foc the prepazation of this mining and reclamation plan amendment including conducting additional geotechnical evaluations of pit slope stability within existing and future mined areas. Surface features such as creeks, roads and buildings are shown on the map of current conditions (i.e. "pre-mining" conditions with respect to this amendment) at the quazry. A power line is shown at the (~ ~ ~~duthern limits of the proposed affected land which is owned by Mountain States Telephone and \ V~ ~y Telegraph Company as part of a rightof--way. Prior to possible mining within 200 ft of the power ~J'~,.4 line, Cooley intends to initiate appropriate notification of the utility owner and institute required ~`y~t' relocation of the line, maintenance of safe distance separation andlor engineering controls to ensure ~k~ ` -.:wrmn+e.mo I-1